Japanese Patent Application Publication No. 2006-24660 discloses a stacked electric double layer capacitor. This stacked electric double layer capacitor includes a capacitor unit as a unit composed of a plurality of cells connected in series, wherein electric energy enters or exits the capacitor unit through a current collector terminal.
FIGS. 7 to 9 show specific construction of the stacked electric double layer capacitor. FIG. 7 is a perspective view of the stacked electric double layer capacitor, FIG. 8 is a side view of the capacitor unit of FIG. 7 as viewed in the direction of an arrow B in which the current collector terminal is not exposed, and FIG. 9 is an enlarged view showing construction of a region C encompassed by a long dashed double-short dashed line in FIG. 8.
As shown in FIG. 7, the capacitor unit 10 is wrapped by an aluminum laminate film 20, the inside is vacuumed, and terminal portions 30c as brought-out parts of two current collector terminals 30 are heat-welded to a heat welded portion 21. These current collector terminals 30 are brought into contact with a current collector plate that is arranged inside a pressure plate 50.
As shown in FIGS. 8 and 9, the current collector terminal 30 includes: a contact portion 30a that is in contact with the current collector plate arranged inside the pressure plate 50; a portion 30b that is perpendicular to the contact portion 30a and perpendicularly bended to a side surface of the capacitor unit 10; and a terminal portion 30c that is perpendicularly bended with respect to the portion 30b, i.e., parallel to the contact portion 30a. The terminal portion 30c is connected to an external circuit not shown.